From 907eeeda8a1f5a43e00e29badabcd32a8d19415e Mon Sep 17 00:00:00 2001
From: Tatsuhiro Tsujikawa <tatsuhiro.t@gmail.com>
Date: Tue, 8 Mar 2016 21:38:15 +0900
Subject: [PATCH] src: Return StringRef from util::get_uri_field

---
 src/h2load.cc |  6 +++---
 src/nghttp.cc | 24 ++++++++++++------------
 src/util.cc   | 12 ++++++------
 src/util.h    |  4 ++--
 4 files changed, 23 insertions(+), 23 deletions(-)

diff --git a/src/h2load.cc b/src/h2load.cc
index dc164b28..14b1fca4 100644
--- a/src/h2load.cc
+++ b/src/h2load.cc
@@ -1396,7 +1396,7 @@ std::string get_reqline(const char *uri, const http_parser_url &u) {
   std::string reqline;
 
   if (util::has_uri_field(u, UF_PATH)) {
-    reqline = util::get_uri_field(uri, u, UF_PATH);
+    reqline = util::get_uri_field(uri, u, UF_PATH).str();
   } else {
     reqline = "/";
   }
@@ -1437,8 +1437,8 @@ bool parse_base_uri(std::string base_uri) {
     return false;
   }
 
-  config.scheme = util::get_uri_field(base_uri.c_str(), u, UF_SCHEMA);
-  config.host = util::get_uri_field(base_uri.c_str(), u, UF_HOST);
+  config.scheme = util::get_uri_field(base_uri.c_str(), u, UF_SCHEMA).str();
+  config.host = util::get_uri_field(base_uri.c_str(), u, UF_HOST).str();
   config.default_port = util::get_default_port(base_uri.c_str(), u);
   if (util::has_uri_field(u, UF_PORT)) {
     config.port = u.port;
diff --git a/src/nghttp.cc b/src/nghttp.cc
index a1705124..af349519 100644
--- a/src/nghttp.cc
+++ b/src/nghttp.cc
@@ -187,7 +187,7 @@ int Request::update_html_parser(const uint8_t *data, size_t len, int fin) {
 
 std::string Request::make_reqpath() const {
   std::string path = util::has_uri_field(u, UF_PATH)
-                         ? util::get_uri_field(uri.c_str(), u, UF_PATH)
+                         ? util::get_uri_field(uri.c_str(), u, UF_PATH).str()
                          : "/";
   if (util::has_uri_field(u, UF_QUERY)) {
     path += '?';
@@ -200,21 +200,20 @@ std::string Request::make_reqpath() const {
 namespace {
 // Perform special handling |host| if it is IPv6 literal and includes
 // zone ID per RFC 6874.
-std::string decode_host(std::string host) {
+std::string decode_host(const StringRef &host) {
   auto zone_start = std::find(std::begin(host), std::end(host), '%');
   if (zone_start == std::end(host) ||
       !util::ipv6_numeric_addr(
           std::string(std::begin(host), zone_start).c_str())) {
-    return host;
+    return host.str();
   }
   // case: ::1%
   if (zone_start + 1 == std::end(host)) {
-    host.pop_back();
-    return host;
+    return StringRef{host.c_str(), host.size() - 1}.str();
   }
   // case: ::1%12 or ::1%1
   if (zone_start + 3 >= std::end(host)) {
-    return host;
+    return host.str();
   }
   // If we see "%25", followed by more characters, then decode %25 as
   // '%'.
@@ -222,9 +221,9 @@ std::string decode_host(std::string host) {
                          ? zone_start + 3
                          : zone_start + 1;
   auto zone_id = util::percent_decode(zone_id_src, std::end(host));
-  host.erase(zone_start + 1, std::end(host));
-  host += zone_id;
-  return host;
+  auto res = std::string(std::begin(host), zone_start + 1);
+  res += zone_id;
+  return res;
 }
 } // namespace
 
@@ -349,7 +348,7 @@ int submit_request(HttpClient *client, const Headers &headers, Request *req) {
   auto scheme = util::get_uri_field(req->uri.c_str(), req->u, UF_SCHEMA);
   auto build_headers = Headers{{":method", req->data_prd ? "POST" : "GET"},
                                {":path", path},
-                               {":scheme", scheme},
+                               {":scheme", scheme.str()},
                                {":authority", client->hostport},
                                {"accept", "*/*"},
                                {"accept-encoding", "gzip, deflate"},
@@ -1255,7 +1254,8 @@ void HttpClient::update_hostport() {
   if (reqvec.empty()) {
     return;
   }
-  scheme = util::get_uri_field(reqvec[0]->uri.c_str(), reqvec[0]->u, UF_SCHEMA);
+  scheme = util::get_uri_field(reqvec[0]->uri.c_str(), reqvec[0]->u, UF_SCHEMA)
+               .str();
   std::stringstream ss;
   if (reqvec[0]->is_ipv6_literal_addr()) {
     // we may have zone ID, which must start with "%25", or "%".  RFC
@@ -2381,7 +2381,7 @@ int run(char **uris, int n) {
         }
         requests.clear();
       }
-      prev_scheme = util::get_uri_field(uri.c_str(), u, UF_SCHEMA);
+      prev_scheme = util::get_uri_field(uri.c_str(), u, UF_SCHEMA).str();
       prev_host = std::move(host);
       prev_port = port;
     }
diff --git a/src/util.cc b/src/util.cc
index 7805a957..784806be 100644
--- a/src/util.cc
+++ b/src/util.cc
@@ -591,13 +591,13 @@ bool fieldeq(const char *uri, const http_parser_url &u,
   return i == len && !t[i];
 }
 
-std::string get_uri_field(const char *uri, const http_parser_url &u,
-                          http_parser_url_fields field) {
-  if (util::has_uri_field(u, field)) {
-    return std::string(uri + u.field_data[field].off, u.field_data[field].len);
-  } else {
-    return "";
+StringRef get_uri_field(const char *uri, const http_parser_url &u,
+                        http_parser_url_fields field) {
+  if (!util::has_uri_field(u, field)) {
+    return StringRef{};
   }
+
+  return StringRef{uri + u.field_data[field].off, u.field_data[field].len};
 }
 
 uint16_t get_default_port(const char *uri, const http_parser_url &u) {
diff --git a/src/util.h b/src/util.h
index 15894816..d03ffd8e 100644
--- a/src/util.h
+++ b/src/util.h
@@ -448,8 +448,8 @@ bool fieldeq(const char *uri1, const http_parser_url &u1, const char *uri2,
 bool fieldeq(const char *uri, const http_parser_url &u,
              http_parser_url_fields field, const char *t);
 
-std::string get_uri_field(const char *uri, const http_parser_url &u,
-                          http_parser_url_fields field);
+StringRef get_uri_field(const char *uri, const http_parser_url &u,
+                        http_parser_url_fields field);
 
 uint16_t get_default_port(const char *uri, const http_parser_url &u);